Replacement medicines could become more expensive, with longer periods of treatment required to bring about the same effect, she added.

Dr Chan said: “Things as common as strep throat or a child’s scratched knee could once again kill.

“Antimicrobial resistance is on the rise in Europe and elsewhere in the world. We are losing our first-line antimicrobials.

“Replacement treatments are more costly, more toxic, need much longer durations of treatment, and may require treatment in intensive care units.

“For patients infected with some drug-resistant pathogens, mortality has been shown to increase by around 50 per cent.

“A post-antibiotic era means, in effect, an end to modern medicine as we know it.”

The stark warning comes shortly after the World Health Organisation published a new book warning of the “global crisis”, entitled “The evolving threat of antimicrobial resistance.”

It reads: “Bacteria which cause disease react to the antibiotics used as treatment by becoming resistant to them, sooner or later.

“A crisis has been building up over the decades, so that today many common and life-threatening infections are becoming difficult or even impossible to treat, sometimes turning a common infection into a life-threatening one.”

The paper blamed the current situation largely on the misuse of antibiotics, which are not prescribed properly and used too frequently and for too long.

It added that an “inexorable increase in antimicrobial-resistant infections, a dearth of new antibiotics in the pipeline and little incentive for industry to invest in research and development” had led to a need for innovation”.

The WHO has now appealed to governments across the world to support research into the antimicrobial resistance.